In recent years, the formerly labor-intensive process of collecting household refuse and recyclable materials has become increasingly automated, as improvements have been made to the vehicles employed in collecting such materials. Modem refuse collection vehicles typically include an integral refuse collection bin and a compaction mechanism for compacting materials in or adjacent to the collection bin. Such vehicles may introduce refuse into the collection bin from the front, rear or side of the vehicle. Some such vehicles include mechanized handling devices which include a holding or grasping assembly for holding a refuse container. These handling devices typically include a container access assembly which is adapted to move the holding assembly into position to grab a container, and to cooperate with the holding assembly to lift and dump the contents of the container in the collection bin of the vehicle. The container access assembly may then be used to return the container to its original position.
These holding assemblies and container access assemblies take many forms. Thus, for example, U.S. Pat. No. 4,401,407 of Breckenridge describes an apparatus which includes a telescoping container access assembly and a holding assembly which includes multiple pivoting arm components. U.S. Pat. No. 4,543,028 of Bell et al. describes an apparatus which includes an rail mounted access assembly that pivots about a horizontal axis to move the container into the dumping position. U.S. Pat. No. 4,566,840 of Smith describes an access assembly that includes a fixed frame portion to which is attached a linkage assembly that carries the holding assembly. U.S. Pat. No. 4,726,726 of Dossena et al. describes a telescoping access assembly to which is attached a holding assembly that rotates about a horizontal axis to dump the contents of a container into the collection bin. U.S. Pat. No. 4,983,092 of Richards describes a pivoting holding assembly that is mounted on a transverse guide rail. U.S. Pat. No. 5,007,786 of Bingman describes a refuse collection system which includes a holding assembly that is mounted on a carriage that rides in a vertical rail assembly to dump the contents of a container. U.S. Pat. No. Re. 34,292 of Bingman et al. describes an articulated boom assembly having a pair of gripping arms mounted on a carriage that moves along the outer arm of the assembly. U.S. Pat. No. 5,391,039 of Holtom describes a refuse loader arm that includes an articulated access assembly having inner and outer limbs that are joined by a parallelogram linkage that holds the holding assembly at a constant angle with respect to the inner limb. U.S. Pat. No. 5,419,671 and U.S. Pat. No. 5,547,332, both of Smith et al., describe a container handling assembly that is mounted on the top of the vehicle adjacent to the collection bin. U.S. Pat. No. 5,470,187 of Smith et al. describes a handling assembly having a fixed boom that pivots about a vertical axis adjacent to the vehicle frame, on which boom is mounted a vertically adjustable container holding assembly.
All of these known assemblies suffer from one or more of various disadvantages. Some of the known systems offer a limited reach in accessing a container. Some are unable to grab a container that is not on the same level as the vehicle. Some raise the container so high during the dumping portion of the operating cycle that the container and the holding portion of the assembly may come into contact with low-hanging power or telephone lines. Some are mechanically complex and difficult to operate. Some protrude from the vehicle on which they are mounted to such an extent that they present a risk of hitting other vehicles, mailboxes or other roadside obstacles. Some are slow to complete their operating cycle, and some are expensive to build and install. It would be desirable if a system could be developed that would overcome these disadvantages.